Delta Arietis
Delta Arietis is a star in the northern constellation of Aries, positioned 1.8 degrees north of the ecliptic. Its identifier is a Bayer designation that is Latinized from δ Arietis, and abbreviated Delta Ari or δ Ari. This star is officially named Botein, pronounced. The apparent visual magnitude of Delta Arietis is 4.35, so it is visible to the naked eye. It has an annual parallax shift of ; corresponding to a distance of about from the Sun. This star is receding from the Sun with a radial velocity of +23 km/s.
Nomenclature
δ Arietis is the star's Bayer designation.It bore the traditional name Botein which is derived from Al Bīrūnī's Al Buṭayn, the diminutive of Al Baṭn, "the Belly". This is the name of a star association consisting of this star, Epsilon Arietis, Zeta Arietis, Pi Arietis, and Rho3 Arietis According to a 1971 NASA catalogue of stars, Al Buṭain was the title for five stars: Delta Arietis, Pi Arietis, Rho3 Arietis, Epsilon Arietis and Zeta Arietis. In 2016, the International Astronomical Union organized a Working Group on Star Names to catalogue and standardize proper names for stars. The WGSN approved the name Botein for this star on 12 September 2016 and it is now so included in the List of IAU-approved Star Names.
In the catalogue of stars in the Calendarium of Al Achsasi Al Mouakket, this star was designated Nir al Botain, which was translated into Latin as Lucida Ventris, meaning "the brightest of the belly".
In Chinese, 天陰, meaning Yin Force, refers to an asterism consisting of Delta Arietis, 63 Arietis, Zeta Arietis, Tau Arietis and 65 Arietis. Consequently, the Chinese name for Delta Arietis itself is 天陰四